Have had the same experiance while over Africa with BA, EK, LH, KLM so maybe it just gets quiet out there some times and its good to know you are not alone when you see fellow travellers at night around.
However recently in bound to Liverpool from Berlin 20/12 and had landing lights on twice while over North Sea while still in cruise, no idea why but we appeared to be skimming through the tops of high cloud so that maybe reason, but I have not had this happen before with other carriers maybe SOP for Easyjet in those circumstances.